Updating array document with MongooseJS and ExpressJS

ObjectController.js

var mongoose = require('mongoose');
var myDocument_schema = require('./ObjectModel');
var db_lnk = 'mongodb://localhost/mydatabase';

exports.Update = function (req, res, next){
  var db = mongoose.createConnection(db_lnk);
  var idDoc = req.param.id; //We get the ID param
  var today = new Date();
  var myDoc = db.model('MyDocuments',myDocument_schema);
  myDoc.findById(idDoc, function(err, doc){
    //Update all the fields
    doc.someValue   : 'This is my new Value';
    doc.someDate    : today;
    doc.someBool    : true;
    //Now insert at the end of the array
    doc.someArray.push({someElement:'Hello', someElement2: "World"});
    //Insert at the begining of the array
    doc.someArray2.unshift({someElement3:"Foo Bar"});
    doc.save(function(err, result){
      if(err){
        console.log("Ups, something wrong");
      }else{
        cosole.log("Ok, now what?");
        //more code
      }
      db.close();
    });
  };
};

ObjectModel.js

var Schema = require('mongoose').Schema;

var myDocumentSchema = new Schema({
  someValue   : String,
  someDate    : Date,
  someBool    : Boolean,
  someArray   : [{
    someElement   : String,
    someElement2  : String
  }],
  someArray2 : [{
    someElement3 : String
  }]
});

module.exports = myDocumentSchema;